Memo to Gerry Adams... Mairia Cahill has not gone away, you know

It is possible that Sinn Fein president Gerry Adams believes that - as he says - he grew up in an apartheid state where Catholics were denied the vote, was a founder member of the civil rights movement, never joined the IRA and - urged on by his teddy bears - worked selflessly and eventually successfully to persuade the wicked Brits to concede equal status to Catholics, thus making it possible for the "undefeated army" to lay down its arms, since that was what they had been fighting for.

I'm not alone in questioning all if not most of that narrative, which is why Mr Adams struggles to have his denials of the allegations Mairia Cahill made against him on Spotlight last week believed unquestioningly by anyone other than his most faithful followers.

Ms Cahill described how – from 1997, when she was 16 – she endured a year of sexual abuse, including rape, by a member of the IRA who had married into her family, how subsequently she was interrogated repeatedly and silenced by the IRA, forced to confront her abuser, and in meetings with Mr Adams, found him horrifyingly insensitive.

I have met Mairia and admire her courage and intelligence – qualities she shares with her cousin Eilis O'Hanlon, who appeared in support of Mairia on Spotlight.

Both women are widely seen as traitors, for they were born into republican aristocracy – great-nieces of the late Joe Cahill, who murdered a policeman in the 1940s and was a founder of the Provisional IRA.

Eilis' late sister Siobhan, a convicted terrorist who became Gerry Adams's personal assistant, was one of those in whom the young Mairia confided and who, she claimed, was part of the cover-up of the rapes.

More shockingly, to those of us who support the police, was the revelation on Spotlight that they took four years to put together an under-investigated prosecution case against Pat Finucane's brother Seamus and others involved in IRA dealings with Mairia. That the case collapsed – as did that against the alleged rapist – was, sadly, no surprise.

SDLP MP Mark Durkan gave disturbing testimony of how he learned that politicians – including Shaun Woodward, one-time Labour Secretary of State for Northern Ireland (who denies it) – were being schmoozed by Sinn Fein's Westminster lobby with a sob-story about attempts by sinister elements to try to damage the peace.

Still reeling from a Dublin by-election in which the SF candidate was unexpectedly beaten by an even more left-wing candidate, Adams is now vulnerable on another flank. The southern media ignored the story until Mairia took it to Dublin, meeting senior politicians and giving media interviews. On social media she has received a few nasty messages and massive support.

In 2009, in response to a shocking report about clerical abuse of children, Sinn Fein called for society "to expose the wrong done to those children and ensure that every step is taken to pursue the perpetrators and those who failed or purposely refused to carry out their duties to protect children and to investigate and prosecute criminals".

When shortly afterwards Liam Adams was accused of raping his daughter Aine, who said her Uncle Gerry had known about it and did nothing, that tune changed to this being "a private family matter".

Over the past few days senior Sinn Fein figures have been hiding from the media or waffling helplessly.

Mary Lou McDonald TD, Mr Adams's golden girl, first made this mystifying contribution: "I take the view on anything that is related to a person who has been or who alleges that they have been abused in any way, that the first issue is around the person themselves."

Under media pressure, she admits she believes Mairia was abused but is desperately trying to defend the party and its leader.

Sinn Fein is in crisis. Not only has Mr Adams been accused twice of protecting republican rapists, but Mairia reports that other women abused by IRA members who are thinking of coming forward.

Mr Adams's depiction of himself as a selfless protector of the innocent is being burnished even as I write. But Mairia Cahill hasn't gone away, you know.